
package com.ruoyi.data;


import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import java.io.IOException;
import java.security.*;
/**
 * 密码转换
 * @author chengY
 * @version 1.0
 */
public class MD5
{
	private final static String DES = "DES";
	private final static String ENCODE = "GBK";
	private final static String defaultKey = "netwxactive";
	private final static String key ="zanysoft";

	/**
	 * 使用 默认key 加密
	 * @param data 待加密数据
	 * @return
	 * @throws Exception
	 */
	public static String encrypt(String data) throws Exception {
//		byte[] bt = encrypt(data.getBytes(ENCODE), defaultKey.getBytes(ENCODE));
//		String strs = new BASE64Encoder().encode(bt);
		String strs = encrypt(data, key);
		return strs;
	}

	/**
	 * 使用 默认key 解密
	 * @param data 待解密数据
	 * @return
	 * @throws IOException
	 * @throws Exception
	 */
	public static String decrypt(String data) throws Exception {
//		if (data == null)
//			return null;
//		BASE64Decoder decoder = new BASE64Decoder();
//		byte[] buf = decoder.decodeBuffer(data);
//		byte[] bt = decrypt(buf, defaultKey.getBytes(ENCODE));
		return decrypt(data, key);
	}

	/**
	 * Description 根据键值进行加密
	 * @param data 待加密数据
	 * @param key 密钥
	 * @return
	 * @throws Exception
	 */
	public static String encrypt(String data, String key) throws Exception {
		byte[] bt = encrypt(data.getBytes(ENCODE), key.getBytes(ENCODE));
		String strs = new BASE64Encoder().encode(bt);
		return strs;
	}

	/**
	 * 根据键值进行解密
	 * @param data 待解密数据
	 * @param key    密钥
	 * @return
	 * @throws IOException
	 * @throws Exception
	 */
	public static String decrypt(String data, String key) throws Exception {
		if (data == null)
			return null;
		BASE64Decoder decoder = new BASE64Decoder();
		byte[] buf = decoder.decodeBuffer(data);
		byte[] bt = decrypt(buf, key.getBytes(ENCODE));
		return new String(bt, ENCODE);
	}

	/**
	 * Description 根据键值进行加密
	 *
	 * @param data
	 * @param key
	 *            加密键byte数组
	 * @return
	 * @throws Exception
	 */
	private static byte[] encrypt(byte[] data, byte[] key) throws Exception {
		// 生成一个可信任的随机数源
		SecureRandom sr = new SecureRandom();
		// 从原始密钥数据创建DESKeySpec对象
		DESKeySpec dks = new DESKeySpec(key);
		// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
		SecretKey securekey = keyFactory.generateSecret(dks);
		// Cipher对象实际完成加密操作
		Cipher cipher = Cipher.getInstance(DES);
		// 用密钥初始化Cipher对象
		cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
		return cipher.doFinal(data);
	}

	/**
	 * Description 根据键值进行解密
	 *
	 * @param data
	 * @param key 加密键byte数组
	 * @return
	 * @throws Exception
	 */
	private static byte[] decrypt(byte[] data, byte[] key) throws Exception {
		// 生成一个可信任的随机数源
		SecureRandom sr = new SecureRandom();

		// 从原始密钥数据创建DESKeySpec对象
		DESKeySpec dks = new DESKeySpec(key);

		// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
		SecretKey securekey = keyFactory.generateSecret(dks);

		// Cipher对象实际完成解密操作
		Cipher cipher = Cipher.getInstance(DES);

		// 用密钥初始化Cipher对象
		cipher.init(Cipher.DECRYPT_MODE, securekey, sr);

		return cipher.doFinal(data);
	}

	public static void main(String[] args){
		String data = "我是需要被加密的数据";
		// 这里的key长度必须大于8位
		String key ="cy135@$^";
		System.out.println("初始数据===>"+data);
		try {
			System.out.println();
			System.out.println(">>>>>>>>>>根据预定秘钥加密后：" + encrypt(data, key));
			System.out.println(">>>>>>>>>>根据预定秘钥解密后：" + decrypt(encrypt(data, key), key));

			System.out.println("==========================================");
			String encrypt = encrypt(data);
			System.out.println(">>>>>>>>>>默认秘钥加密后："+encrypt);
			System.out.println(">>>>>>>>>>默认秘钥解密后："+decrypt(encrypt));
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

}